1. Field of the Invention
The present invention relates generally to a method of fabricating a MIMCAP (a capacitor (CAP) formed by successive layers of metal, insulator, metal (MIM)) and a thin film resistor at the same level. The subject invention also pertains to a method of fabricating a MIMCAP and thin film resistor at same level, and a novel integration scheme for BEOL (back-end-of-line processing) thin film resistors which positions them closer to FEOL (front-end-of-line processing) devices.
2. Discussion of the Prior Art
In the prior art, thin film resistors are currently incorporated in the BEOL (back-end-of-line processing) levels, typically between the MX (M1/MT) metal levels or at the thick interconnect level, wherein MX designates any metal layer. Because the thin film resistors are so far away from the transistor devices, the wiring is often quite complicated and lengthy, adding to the interconnect delay of typical circuits of any type such as amplifier circuits and oscillator circuits. Because of these concerns and problems, it is desirable to position the thin film resistors closer to the FEOL (front-end-of-line processing) devices, which are generally basic building block circuits.
The wiring path for a prior art thin film resistor using the current prior) art integration scheme is CA (contact metal)-->M1 (metal layer 1)--->V1 (via)--->MT (metal layer 2,3, etc.)--->V1 (via)--->K1 (thin film resistor) and back in the reverse order to CA.